Sharpening implement



jam. 23, 1945. E, PROBST SHARPENING IMPLEMENT Filed April 26, 1944 INVENTOR f' me Prorit, W W;

ATTORNEY.

Patented Jan. 23, 1945 UNITED STATES PATENT "OFFICE 4 Claims.

In my application for patent Serial No. 507,385 a tool-sharpening implement is set forth complete in two parts-a substantially cylindrical element free to rotate around its own axis and having end surfaces substantially perpendicular to such axis and one of which is an abrading surface, and a case or holder :orf stiff material wholly exterior of said element and thereby confining the same against escape from the holder in any direction and to rotate therein around its said axis, said holder having a tool guideway exposing the abrasive surface, and an aperture exposing the perimeter, of said element. In the sharpening operation, the tool is positioned in, and it or the device reciprocated lengthwise of, the guideway, the abrading surface, being planiform, acting in that case to develop the surface being ground planiform; said element is rotative in the holder, as by effort applied to the exposed portion of its perimeter, so that difierent portions of its surface may be exposed to the guideway.

According to the present invention the implement is also complete in two parts, a holder and the abrading element, the latter being confined in the holder and rotatable therein without the presence of a third part to provide its pivot; but said element is of bulbous form, as spherical, whereby the implement becomes useful for hollow grinding, [for instance, in sharpening hollow-ground or channeled skate-runners, and if said element is spherical it may be rotated around any axis so that any portion of its entire surface may be exposed to the guideway.

In the drawing,

Fig. 1 is a side elevation; and

Fig. 2 an end elevation of the present implement, the holder being partly broken away at the right to show one of its bearing apertures.

The bulbous element I here has the shape of a ball or sphere; it may be wholly composed of abrading substance but, as shown, at least has its surface abrasive, here entirely.

The case or holder is formed generally the same as in the example of my said application, or from a generally oblong blank of stiff sheet material bent to form a bottom wall 2, a pair of spaced walls 3 upstanding from the bottom wall, and a fourth wall formed by bending the upper marginal portions of walls 3 toward each other but so as to leave a slot to form a guideway; preferably the marginal portions of the portions 4 are bent upwardly to form lips 5 spaced from each other. The two walls 3 are formed with apertures '6, opposed to each other and here circular.

The abrading element, as shown, is contained in the holder and has diametrically opposite portions la thereof projecting through the apertures 6, whereby it is confined in the holder. But said portions sufficiently loosely fit the apertures, as shown at the right of Fig. 2, so that said element is free to be rotated, at least around the axis of said apertures, as by efiort applied to their exposed portions, though in the present case said element (being at least generally spherical) may be rotated around any axis.

In using the implement to sharpen the two edges, as la, of say a skate-blade I it is held in one hand of the operator and, with the blade held in the other hand and entered to the guideway and against said element, the device or blade is reciprocated lengthwise of the blade, said element being meanwhile grasped and thus held from rotation except when it may be rotated to bring a fresh portion of its perimeter into action. The bulbous form of said element of course accomplishes hollow-grinding or the sharpening of the actual edges la. In the present example, said element being spherical and its entire surface abrasive, it may be rotated around any axis to bring any portion of its perimeter (here wholly abrasive) into effect.

However, the following being true of the example set forth, to wit, that the device is complete in two parts, a holder of stiff material and a bulbous element (as I); that the holder includes spaced supporting portions (as 3) having what I term bearing apertures (as 6); that said element is arranged between and has limited portions thereof (as la) projecting into and journaled in said apertures and coacting therewith to confine said element in the holder; that said element, for at least that segment thereof which exists between its said limited portions, has its p'erimeter abrasive; and that said holder has a tool guideway (here formed by the lips 5) exposing the abrasive perimeter of said element, I claim my improved device accordingly.

Having thus fully described my invention, what I claim is:

1. A sharpening implement comprising a holder of stiff material including opposed spaced supporting portions respectively having opposed bearing apertures, and a generally bulbous element arranged between and having opposed limited portions thereof projecting into and journaled in said apertures and coacting therewith to confine said element in the holder, said element for at least the segment thereof which exists between its said limited portions having its perimeter abrasive guideway exposing element.

2. A sharpening implement comprising a holder of stiff material including opposed s-pac'ed supporting portions respectively having opposed bearing apertures, and a generally bulbous element arranged :between and having opposed convex portions of its perimeter projecting into and journaled in said apertures and coacting therewith to confine said element in the holder, said element for at least the segment thereof which exists between its said limited portions having its perimeter abrasive and said holder having a tool guideway exposing the abrasive perimeter of said element.

3. A sharpenin implement comprising a holder of stiff material including opposed spaced. supporting portions respectively having opposed bearing apertures, and a generally spherical element arranged between and having opposed limited portions thereof projecting into and jourand said holder having a tool the abrasive perimeter of said 20 of said element.

naled in said apertures and coacting therewith to confine said element in the holder, said element for at least the segment thereof which exists between its said limited portions having its perimeter abrasive and said holder having a tool guideway exposing the abrasive perimeter of said element.

4. A sharpening implement comprising a holder of stiff material including opposed spaced supporting portions respectively having opposed bearing apertures, and a generally spherical element arranged between and having opposed convex portions of its perimeter projecting into and journaled in said apertures and-coasting therewith to confine said element in the holder, said element for at least the segment thereof which existsbetween its said limited portions havin its perimeter abrasive and said holder having a tool guideway exposing the abrasive perimeter EMMET PROBST. 

